Have you installed or tried any other firewall-related software recently? It’s not usual for our firewall to just not turn on at all.
With the Windows Firewall API is very reliable and relatively simple. It’s quite strange it would not turn on at all unless another app may have modified the API rules or settings somehow.
You mention you want to back up your rules. Did you modify the Windows Firewall manually at one point and is that what you want to back up, or do you just want to back up GlassWire’s rules?
I would not recommend backing up GlassWire’s rules because something is clearly very wrong here and it’s probably due to the rules with Windows Firewall.